How I can escape string in app?

[ghost]

I am querying on App, but I can't escape string
Example:
->where('u.full_name="' . $sUserName. '")
in normal way, I can use $this->escape($sUserName), but function escape is missing on Model.
Thanks for support.

[ghost]

I also found another problem:
In mail controller, when I scroll down, ajax still load and message "No messages found here." append again and again.
http://ngon.work/mail_error.png

[DonnaScriptTechs]

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